V110C3V3C50BL Datasheet, PDF (9/12 Pages) Vicor Corporation – DC-DC Converter Module

SECONDARY CONTROL - SC PIN
Output Voltage Programming
The output voltage of the converter can be adjusted or
programmed via fixed resistors, potentiometers or voltage
DACs. See Figure 8.
Error
Amp
1 kΩ
0.033 μF
1.23 V
+OUT
SC
–OUT
RU
Trim Up
R_D
Trim Down
Load
R_D (ohms)
=
1,000 Vout
Vnom – Vout
R_U (ohms)
=
1,000 (Vout –1.23) Vnom
1.23 (Vout – Vnom)
– 1,000
Figure 8 — Output voltage trim down and trim up circuit.
Trim Down
1. This converter is not a constant power device – it has a
constant current limit. Hence, available output power is
reduced by the same percentage that output voltage is
trimmed down. Do not exceed maximum rated output current.
2. The trim down resistor must be connected between the SC
and pins. Do not bypass the SC pin directly with a
capacitor.
Trim Up
1. The converter is rated for a maximum delivered power. To
ensure that maximum rated power is not exceeded, reduce
maximum output current by the same percentage increase in
output voltage.
2. The trim up resistor must be connected between the SC
and pins. Do not bypass the SC pin directly with a
capacitor.
3. Do not trim the converter above maximum trim range
(typically +10%) or the output over voltage protection
circuitry may be activated.
Trim resistor values calculated automatically:
On-line calculators for trim resistor values are available on the
vicor website at:
asp.vicorpower.com/calculators/calculators.asp?calc=1
Resistor values can be calculated for fixed trim up, fixed trim
down and for variable trim up or down.
110 V Micro Family
Page 9 of 12
Rev 3.0
07/2014
110 V Input
PARALLEL BUS - PR PIN
Parallel Operation
The PR pin supports paralleling for increased power with N+1
(N+M) redundancy. Modules of the same input voltage, output
voltage, and power level will current share if all PR pins are
suitably interfaced.
Compatible interface architectures include the following:
AC coupled single-wire interface. All PR pins are connected
to a single communication bus through 0.001 µF (500 V)
capacitors. This interface supports current sharing and is fault
tolerant except for the communication bus. Up to three
converters may be paralleled by this method. See Figure 9.
Transformer coupled interface. For paralleling four or more
converters a transformer coupled interface is required. See
Figure 10.
For details on parallel operation please refer to the
Design Guide & Applications Manual for Maxi, Mini, Micro Family.
4.7 nF
+
+IN
0.2 µF
0.001 µF _Z1*
PC
Module 1
PR
–
–IN
Low inductance
ground plane
or bus
4.7 nF
4.7 nF
+IN
0.2 µF
0.001 µF _Z1*
PC
Module 2
PR
Parallel
Bus
–IN
4.7 nF
Figure 9 — AC coupled single-wire interface.
* See Maxi, Mini, Micro Design Guide.
4.7 nF
+
+IN
0.2 µF
T1 _Z1*
PC
Module 1
PR
–IN
–
4.7 nF
4.7 nF
+IN
0.2 µF
T2 _Z1*
PC
Module 2
PR
–IN
Parallel
Bus
4.7 nF
Figure 10 — Transformer-coupled interface.
vicorpower.com
800 927.9474